How long, timewise, do you have to hold the charge on the capacitor before the flash lamp is triggered? It seems to me that any hold time (which you alluded to) would preclude using contacts on the power switch to dicsharge the cap.

 

Hi Ali,
glad to have helped,
hope it works out alright.

Hi Nigel,
in that situation i spose a bleeder would not matter
if the flash were used straight-away, but it would
affect it if much time elapsed, maybe setting up the
shot, or some such.

Regards, John

 

If it is paramuont to have no load then don't use bleeder resistor.
Use small AC relay with coil wired before the rectifier.
Use normally closed contact to short the DC side of the circuit
(maybe through resistor). This way your DC side will not be
loaded during tests and it will be very quickly discharged.
To prevent short circuit on powerup and not waste those diodes,
use timing relays normally open contact to turn on the rectifier
circuit.
Haaahhhh... to expencive, I would probably just use relay
and put small lightbulb in series with normally closed contact.

8)

Attached Images

test_115.gif (2.0 KB, 113 views)

 

Only if you unplugged it! - and why would you?.

That's also assuming it's a camera flash, and not a strobe, that wasn't made clear - was it?.